If you want to write an email to a friend you must have internet connection, which is colloquially known as being on line (en línea). If you do not have connection you will not be able to send the email.
Therefore, the answer is that you should <u>be on line</u> or:
<h2>En línea
</h2>
If you have a device (equipo) with a good internet connection, it does not matter if you are in a meeting (reunión) orin a pool (una piscina).
Since Mrs. Dombey reacts with surprise to her husband simply calling her "my dear," we can infer that Mr. Dombey is usually formal and distant to his wife.
